Actively-cooled plasma electrode for long pulse operations in a cesium-seeded negative ion source

Fujiwara, Yukio; Watanabe, Kazuhiro; Okumura, Yoshikazu; Trainham, R.*; Jacquot, C.*

Review of Scientific Instruments, 76(1), p.013501_1 - 013501_5, 2005/01

https://doi.org/10.1063/1.1823611

A new actively-cooled plasma electrode has been developed for long pulse operation in a cesium-seeded negative ion source. To keep the electrode temperature at about 300 C, which is optimum range of temperature to enhance cesium effects, the electrode cooling structure has been designed using three-dimensional numerical simulation assuming that the heat flux from the source plasma was 15 W/cm. Water cooling tubes were brazed to the plasma electrode substrate with spacers made of stainless steel which acts as a thermal resistance. The fabricated plasma electrode has been tested in a cesium-seeded volume negative ion source called Kamaboko source. The temperature of the electrode reached 280 C for the arc power of 41 kW, which is operating condition required for producing D- beams with current densities exceeding 20 mA/cm. It was demonstrated that the actively-cooled plasma electrode is applicable to long pulse operations, meeting the temperature requirement for optimizing the surface-production process of negative ions in the cesium seeded ion source.

A Frame-cooled plasma grid for long pulse operations in a cesium-seeded volume negative ion source

Fujiwara, Yukio; Okumura, Yoshikazu; Watanabe, Kazuhiro; Trainham, R.*; Jacquot, C.*

Review of Scientific Instruments, 73(2), p.298 - 304, 2002/02

https://doi.org/10.1063/1.1435845

no abstracts in English

Beamlet-beamlet interaction in a multi-aperture negative ion source

Fujiwara, Yukio; Hanada, Masaya; Okumura, Yoshikazu; Watanabe, Kazuhiro; Kawai, Kenichi*

Review of Scientific Instruments, 71(8), p.3059 - 3064, 2000/08

https://doi.org/10.1063/1.1305515

no abstracts in English

Hydrogen negative ion beam acceleration in a multiaperture five-stage electrostatic accelerator

Watanabe, Kazuhiro; Fujiwara, Yukio; Hanada, Masaya; Kashiwagi, Mieko; Kitagawa, Tadashi*; Miyamoto, Kenji; Morishita, Takatoshi; Okumura, Yoshikazu; Takayanagi, Tomohiro; Taniguchi, Masaki

Review of Scientific Instruments, 71(2), p.1231 - 1233, 2000/02

https://doi.org/10.1063/1.1150434

no abstracts in English

Experimental study on the influence of radiation on high-voltage insulation gases

Fujiwara, Yukio; Inoue, Takashi; Miyamoto, Kenji; Miyamoto, Naoki*; Ohara, Yoshihiro; Okumura, Yoshikazu; Watanabe, Kazuhiro

JAERI-Research 99-071, p.33 - 0, 1999/12

JAERI-Research-99-071.pdf:1.18MB

no abstracts in English

Beamlet interaction in multi-aperture negative ion source

Fujiwara, Yukio; Hanada, Masaya; Kawai, Kenichi*; *; Miyamoto, Kenji; Okumura, Yoshikazu; Watanabe, Kazuhiro

JAERI-Research 99-013, 32 Pages, 1999/02

JAERI-Research-99-013.pdf:1.51MB

no abstracts in English

Development of a multiaperture, multistage electrostatic accelerator for hydrogen negative ion beams

Watanabe, Kazuhiro; Fujiwara, Yukio; Hanada, Masaya; Inoue, Takashi; Miyamoto, Kenji; Miyamoto, Naoki*; Ohara, Yoshihiro; Okumura, Yoshikazu

Review of Scientific Instruments, 69(2), p.986 - 988, 1998/02

https://doi.org/10.1063/1.1148619

no abstracts in English

Steady-state operation of an ampere-class hydrogen negative ion source

Okumura, Yoshikazu; Hanada, Masaya; Miyamoto, Naoki*; Miyamoto, Kenji; Fujiwara, Yukio; Watanabe, Kazuhiro

Dai-9-Kai Ryushisen No Sentanteki Oyo Gijutsu Ni Kansuru Shimpojiumu (BEAMS1998), p.101 - 104, 1998/00

no abstracts in English

Electro-static beam steering mechanism for a high current negative ion beam consisting of multi-beamlets

Hanada, Masaya; Fujiwara, Yukio; Watanabe, Kazuhiro; Okumura, Yoshikazu

Dai-9-Kai Ryushisen No Sentanteki Oyo Gijutsu Ni Kansuru Shimpojiumu (BEAMS1998), p.97 - 100, 1998/00

no abstracts in English

Development of a 1MeV H beam accelerator for neutral beam injector

Watanabe, Kazuhiro; Fujiwara, Yukio; Hanada, Masaya; Inoue, Takashi; Miyamoto, Kenji; Miyamoto, Naoki*; Okumura, Yoshikazu; Sato, Kazuyoshi

Fusion Technology 1998, 1, p.493 - 496, 1998/00

no abstracts in English